quarta-feira, 30 de março de 2016

This is a guest post by Dr. Amy Solomon and Dr. Gil Compo of the NOAA Earth System Research Laboratory and the Cooperative Institute for Research in Environmental Sciences of the University of Colorado-Boulder. Both scientists sit within the Physical Sciences Division, which took on a leading role in the El Niño Rapid Response Campaign. They excel at improving our process-based understanding of the models and developing reanalysis datasets, which are critical to understanding and predicting weather and climate.

The ongoing El Niño of 2015-2016 is a historically strong event, the likes of which is only seen once or twice during a scientific career. Not wanting to let this opportunity pass by, scientists from NOAA and NASA have embarked on an unprecedented and exciting mission to observe this El Niño like no other El Niño has been observed before! From January to March 2016, scientists have been collecting data in a notoriously data-sparse region of the Pacific via Gulfstream jets, high-tech unmanned aircraft, ship cruises, weather balloon launches, and instruments dropped right out of aircraft. This effort is known as the El Niño Rapid Response campaign.

Tracks of all 23 research flights with the NOAA Gulfstream-IV aircraft out of Honolulu, Hawaii during the El Niño Rapid Response campaign from January - March 2016. Research flights were meant to circle massive thunderstorm systems in the central and eastern tropical Pacific Ocean. An example GOES satellite image from February 25, 2016 is shown to give an example of the location and scale of the thunderstorms. Conditions varied daily. NOAA Climate.gov image based off image courtsey of Matt Newmann (CU/CIRES and NOAA/ESRL) and NASA.

The deluge that wasn’t

Why study this El Niño? As discussed in detail in previous blog entries, one significant way El Niño impacts the global climate is through changes in atmospheric wave forcing and large-scale circulations like the Walker Circulation and Hadley Circulation, which then shift the pathways taken by storms around the world. During the 1997-1998 El Niño, the North Pacific stormtrack was shifted southeastward, directing moisture-carrying storms toward California. This caused 13.68 inches of rain to fall in downtown Los Angeles in 1998—the wettest February since records began 130 years before.

There was, therefore, significant concern about the impact of the next big El Niño on California precipitation. By standard measures, the 2015-2016 El Niño has been tied with 1997-98 as the warmest El Niño in the instrumental record. However, only 0.79 inches of rainfall fell during February 2016 in downtown Los Angeles. To date, March 2016 rainfall totals are also significantly below average.

domingo, 27 de março de 2016

When it comes to climate change, the science is in and the debate is over.

Natal - Brazil / Photo: Canindé Soares

But sometimes when you’re studying the science behind climate change, it’s easy to lose track of the story. Climate change isn’t just a hockey stick graph. It isn’t just global temperature projections or satellite records. Climate change is a story about humans, and it’s a daily reality felt by many.

The headlines have been all about sea-level rise lately. For #ScienceSunday, let's set sail and look at the facts! pic.twitter.com/rg0xt1Ucux — Climate Reality (@ClimateReality) February 28, 2016

Every week, Climate Reality hosts a series on Twitter called #ScienceSunday, where we make the latest climate science simple, one tweet at a time. Recently, we broke down two new studies on sea-level rise – and what they mean for people – with help from our friends at Climate Central. If you missed it because you were taking it easy like Sunday morning, here’s a recap of what happened.Today, sea levels are rising faster than at any time in the last 2,800 years.

#ScienceSunday: Today, sea levels are rising faster than at any time in the last 2,800 years https://t.co/8Q6eDd6SoC pic.twitter.com/4m92CBlvwn — Climate Reality (@ClimateReality) February 28, 2016

One of the authors of the new study cited in this graphic, Professor Stefan Rahmstorf, said accelerated sea-level rise “was to be expected, since global warming inevitably leads to rising seas.” Here’s a quick break down of what he means:

Carbon pollution from fossil fuel burning and industry is at an all-time high, and both atmospheric carbon dioxide levels and global temperatures have increased dramatically since the Industrial Revolution. Carbon pollution traps more and more heat in our atmosphere, and these warmer temperatures cause glaciers to melt and sea water to expand – leading to sea-level rise.

Sea levels are rising faster than at any time in almost 3,000 years – and the reason why is clear: human-caused climate change.Sea-level rise is accelerating and worsening coastal flooding worldwide.

Sea-level rise is happening at a shocking rate. According to NASA’s latest measurements, it’s rising by 3.41 mm per year globally. So there’s a little more water, what’s the big deal? Well, we’re already starting to see dangerous effects like major spikes in coastal flooding worldwide, and researchers have attributed more and more of this flooding to climate change.There are human fingerprints on thousands of US coastal floods, according to these studies.

#ScienceSunday: There are human fingerprints on thousands of US coastal floods. New study: https://t.co/Ahi6KBQJdS pic.twitter.com/F0hyU72uSM — Climate Reality (@ClimateReality) February 28, 2016

While a huge range of causes can contribute to sea-level rise, these researchers have found that human-caused climate change often tipped the balance in US coastal flooding events. For example, in Wilmington, North Carolina they estimate that there have been 795 days of coastal flooding since 1950 and an incredible 613 have been categorized as human-caused. That means over 75 percent of coastal flood days would not have happened without climate change, according to this study.When we act on climate, we protect our cities from sea-level rise.

The United Nations Environmental Programme estimates that half of the world’s population lives within 60 kilometers (about 37 miles) of a coast – and three-quarters of all major cities are on a shoreline. If we continue to burn dirty fossil fuels at ever higher rates (“business as usual”), the world’s average temperature is expected to be 2 – 7°C higher than pre-industrial levels. As we mentioned earlier, higher temperatures mean higher sea levels creeping up on great cities from Boston to Bombay.

We took a huge step in the right direction to help mitigate rising sea levels last December. At the UN’s COP 21 climate conference in Paris, representatives from 195 countries across every corner of the world reached a landmark global agreement to reduce greenhouse gas emissions and keep global warming under 2°C.

segunda-feira, 21 de março de 2016

This global celebration of forests provides a platform to raise
awareness of the importance of all types of forests and of trees
outside forests.
Forests cover one third of the Earth's land mass, performing vital
functions around the world. Around 1.6 billion people - including more
than 2,000 indigenous cultures - depend on forests for their livelihood.
Forests are the most biologically-diverse ecosystems on land, home to
more than 80% of the terrestrial species of animals, plants and
insects. They also provide shelter, jobs and security for
forest-dependent communities.
Yet despite all of these priceless ecological, economic, social and
health benefits, global deforestation continues at an alarming rate - 13
million hectares of forest are destroyed annually. Deforestation
accounts for 12 to 20 percent of the global greenhouse gas emissions
that contribute to climate change.

Celebrating forests and water

Every year on the International Day of Forests we celebrate the ways in
which forests and trees sustain and protect us. This year we are
raising awareness of how forests are key to the planet’s supply of
freshwater, which is essential for life.

A resident of the National Tapajos Forest collects wild foliage for preparing a meal. UN Photo/Eskinder Debebe

Did you know?

About one-third of the world’s largest cities obtain a
significant proportion of their drinking water directly from forested
protected areas

Nearly 80 percent of the world’s population – 8 out of 10 people - is exposed to high levels of threat to water security

Improved water resource management can show considerable economic gains

Forests act as natural water filters

Climate change is altering forests role in water flows and the availability of water resources

Forests have a crucial role in building and strengthening resilience

Special Event

The theme of the 2016 International Day of Forests is “forests and
water”. To mark the Day, a joint celebration of the International Day
of Forests and World Water Day will be held on Monday, 21 March 2016
(10:00 to 13:00) in the Economic and Social Council Chamber.
The event entitled “Forests and Water | Sustain Life and
Livelihoods” will raise awareness of the interconnections between
forests and water and their contributions to the implementation of the
2030 Agenda for Sustainable Development.
The UNFF Secretariat and UN-Water are organizing the event, in collaboration with the Government of Sweden.2016 International Day of Forests Program
More information on the Day is available at the UN Forum on Forests.

terça-feira, 15 de março de 2016

On World Water Day, people everywhere show that
they care and that they have the power to make a difference. They get
inspired by information and use it to take action and change things.
This year many will focus on the power that water and jobs have to
transform people’s lives. Nearly all jobs are related to water and those
that ensure its safe delivery. But today, millions of people who work
in water are often not recognized or even protected by basic labour
rights. This needs to change. Read More